It concerns me that the Vanagon Tire
selection process is difficult and confusing to so many.
I wanted to break down the requirements into something that is understandable,
makes sense and is backed up by fact.
Disclaimer: This is the decision process "I USE" to determine safe tires for
my Van and recommendations for friends.
The objective is to select a known "SAFE" tire, rather than a tire that "JUST GETS BY".The intent here is to share the research
I've done and encourage discussions that will help us all better understand this
important safety related topic.The more informed we are,
the better choices we make.

The above
"Recommended
"Minimum"
Tire Specifications" are the result of looking at the specifications of
the original equipment tires, vehicle weight capacity specifications and
"DOT" US Department of Safety Tire Standards.One of the most
important numbers to keep in mind as we proceed is .... 1580
lbs.I will show that each rear tire
needs to be able to carry a minimum of 1580 lbs of weight when properly
inflated.We will look at
Tire Parameters, Silver Sticker Data, Gross Vehicle Weight Ratings, Original Equipment
Tires and Load Inflation Tables.Let's start with
understanding,>
Basic Tire ParametersTire Parameter
Definitions > Click Here

Taking the
Heaviest "GAWR axle rating (rear) of each vehicle you divide by 2 to get per tire data.

Vanagon & Camper ... GAWR Rear 2866 / 2 =
1433 lbs
on each rear wheel if loaded to capacity
Syncro Vanagon & Camper ... GAWR Rear 3042 /
2 = 1521 lbs on each rear wheel if
loaded to capacity* Note ...
Adventurewagen's are an exception and are actually heavier on the
front axle.Here's where
some folks stop.They assume that if they buy a
tire rated to carry the maximum rated weight capacity they would
be OK.Not true ..
please read on.1433 lbs would translate into a
Load Index 93 tire1521 lbs would translate into a
Load Index 95 tire.Load Index Table
> Click HereLet's look at the actual
Vanagon
Original Equipment (OE) tires and their specifications .

> Specifications of
the Original Equipment Tires

With help from list members
and friends I was able to locate several examples of the OE Tire's VW
used from 1984 - 1991.VW Vanagon Original Equipment Tires 1984 - 1991
> Click HereComments:1) As you can see VW used tires with
load ratings of 1580, 1710 & 2270 lbs. - The lowest
load rated tire was, * Size:
205/70R14 97R* Load Range 97* Max Load Capacity: 1580 lbs* Max Inflation Pressure:: 40 psiNotice that this tire has a Max load
Capacity of 1580 lbs.Remember our vans weigh
1433 lbs& 1521 lbs at each rear tire if
loaded to capacity.
So why use a tire with a 1580 lb rating?This
question will be answered in more detail below in the "Load
Inflation Tables for the Original Equipment Tires with Silver Sticker
Data"section.But wait here's more.The
205/70R14 97R VW used was a "special"
passenger car tire.This might lead some people to assume
they can use passenger car tires instead of Light Truck tires on a
Vanagon. However there are
two factors to consider.1) This OE tire had a "Reinforced
sidewall. In today's tire market , passenger car tires with a
reinforced sidewall will have either a XL or RF designation.
Example 305/50R20 XL or
305/50R20 RF.Light Truck tires by the nature of
their design already have reinforced sidewalls and thus the XL & RF
designations do not apply.
2) The second issue and perhaps the
least understood, in using a passenger Car tire on a Light truck
application is the 9% rule.What the heck is this .... Using passenger car tires on light
trucks should be approached with caution. The varied service that a
light truck undergoes and because these vehicles have a higher center
of gravity and greater probability of being overloaded than passenger
cars means that the rated load-carrying capacity of a passenger car
tire used on it is reduced. When referencing a passenger car tire for
light truck use, decrease the tires load capacity by 9%Where does this
9% rulecome from?DOT FEDERAL
MOTOR VEHICLE SAFETY STANDARDSHere's the full
document
Click HereHere's an clip
>>>>

PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS"When passenger
car (P-metric) tires are installed on an MPV, truck, bus, or trailer,
each tire’s load rating is reduced by
dividing it by 1.10"Most
if not all the tire manufactures will have reference to this rule in
the Tech sections of their web sites.A few examples.Yokohama
TireTire Safety.com
TireRack

Therefore
you would need a Passenger Car tire that meets or exceeds these
spec's, * XL or RF designation.* Load Range 100* Max Load Capacity: 1604 lbs* Max Inflation Pressure:: 40 psiThere are very few
passenger tires that meets or exceeds these specifications.If you are aware of such tires, please
let me know.I DO NOT
RECOMMEND THE USE OF A PASSENGER CAR TIRE ON A VANAGON> Load Inflation Tables for the Original Equipment Tires with Silver
Sticker DataWhy is this important?A load inflation table shows
us the weight carrying capacity of a tire at various inflation values.
The table below combines Silver Sticker Data,
OE Tire Specs and Load Inflation data into one table .This table enables us to see the load capacity VW determined was appropriate for
the Vanagon. OE Tire Load Inflation Table >
Click HereComments:1) In the table you can see the
Load Carrying Capacity of each tire when
inflated to VW's Recommended Inflation Values. Notice that the Load Inflation Table values for the rear tires always shows inflations that are capable of
carrying a load of 1580 lbs
or Higher.Refer back to the Vehicle Weight
Carrying Capacities data.Looking at the GAWR data we can
conclude,A 2WD
Vanagon or Camper
would see 1433 lbs on each rear wheel if loaded to capacity.And a 4WD
Syncro Vanagon or Camper
would see 1521 lbs on each rear wheel if loaded to capacity.So if we are
carrying
those weights, why did VW use tires with slightly higher capacities and inflate them to
carry a load
of 1580 lbs
- MINIMUM.In
the tire industry they refer to this as "Reserve Capacity".
Perhaps another way to look at it is as a "SAFETY MARGIN".The weight each rear tire
could be subjected to with a full capacity load is
dead weight and does not factor in driving stresses,
emergency maneuvers,
handling or ride characteristics.A vehicle and tire
manufacturer working together develop the
tire design that will produce the most satisfactory
results.In
our case VW determined a tire with a Minimum Load Capacity of
1580 lbs
was the correct choice for this vehicle.
So for any Vanagon ... we want a
"MINIMUM of a
1580 lb rated tire" which equates to a Load Index of 97 .

>
Specs on
a sampling of
today's most popular Vanagon Tires

A good "sanity
check" would be to take a look at some of the most popular tires used by
Vanagon owners today.

Lets see how these tires
stack up against the

Recommended
"Minimum"
Tire Specifications > Click Here-
Load RangeAn indicator of
sidewall strength. The load range or ply
rating branded on a tire's sidewall helps identify its strength and
ability to contain air pressure. Load ranges are identified in
ascending alphabetical order for light truck tires (the further along
the letter is in the alphabet, the stronger the tire and the greater
amount of air pressure it can withstand and load it can carry). Before
load ranges were adopted, ply ratings were used to identify the relative
strength of light truck tires with higher numerical values assigned to
tires featuring stronger, heavier duty constructions.

Today's load range/ply ratings do not count the actual number of body
ply layers found inside the tire, but indicate an equivalent strength
based on early bias ply tires. Most radial passenger tires have one or
two body plies, and light truck tires, even those with heavy duty
ratings (10-, 12- or 14-ply rated), actually have only two or three
fabric body plies, or one steel ply.Source - TireRack.com.

We want a minimum
Load Range "C or 6 Ply" for a Vanagon

PLY

Load Rating

2

A

4

B

6

C

8

D

10

E

- Max
Inflation PSIYour tires support the
weight of your vehicle, right? Well, they don't! It's the air pressure
inside them that actually supports the weight. Maintaining sufficient
air pressure is required if your tires are to provide all of the
handling, traction and durability of which they are capable.This is an indicator of
the overall strength of the tire (as in structural integrity, not load
carrying ability).Although VW originally used one
tire with a Max Inflation value of only 40 PSI ... as I stated earlier .. this was a
special "Reinforced
Sidewall Passenger Car Tire.

Hopefully after reading through this
material you now have a good understanding on the specifications of the
original equipment tires VW used, the carrying capacities of these
vehicles, and a better understanding of how to
select a "Safe Tire" for your own Van.Lastly, I would like to extend a
special thanks to so many people within our VW community and beyond.
Each was very willing to share their
perspective, knowledge and put up with my constant questioning on this
subject.

I do not mean to imply that they all agree with every conclusion I have
made.